Do" was written by series creator, executive producer and lead actress Tina Fey, and directed by series producer Don Scardino. This was Fey's twenty-first writing credit, and Scardino's twenty-seventh directed episode. "I Do Do" originally aired on NBC in the United States on May 21, 2010, as the twenty-second episode and season finale of the show's fourth season and the 80th overall episode of the series. This episode of 30 Rock was filmed on March 16, April 7, and April 8, 2010. Saint Cecilia's Catholic Church in Greenpoint, Brooklyn served as the church for Floyd and Kaitlin's wedding. In March 2010, it was confirmed that actor Matt Damon would guest star on 30 Rock, and in this season finale episode, he played Carol, an airline pilot and love interest for Fey's character, Liz Lemon. In December 2009, Entertainment Weekly informed Damon that he was at the top of Fey's guest star wish list for the show. When told about this, Damon, a fan of the show, responded "I would do [30 Rock] in a heartbeat if they asked me to come on. She should call my people – or even better me. Or I could call her. Let's make this happen." Damon had worked with Alec Baldwin in the 2006 feature films The Departed and The Good Shepherd. Damon's role on the show made it his second prime-time television appearance following his guest spot on Will & Grace—a series that previously aired on NBC—in 2002. When asked if he would return as Carol in the show's fifth season, Damon said "If they'll have me, I would love to pop in and see the gang again. I had a great time doing it." In "I Do Do", actors Elizabeth Banks, Will Forte, Julianne Moore, Michael Sheen, and Jason Sudeikis reprised their roles as Avery Jessup, Paul, Nancy Donovan, Wesley Snipes, and Floyd DeBarber, respectively. This episode concluded Jack's love triangle arc with Avery and Nancy, which first began in "Lee Marvin vs. Derek Jeter", after it was revealed that Avery was pregnant with Jack's child, and Jack ultimately choosing Avery. Show producer and writer Paula Pell made an appearance on the episode as Paula Horneberger, the wife of Pete Horneberger, played by Scott Adsit. In one scene of this episode, Jack sees Avery and tells her he wants to be with her, though, music is played in the background as Jack